Intel MD566X manual Registers, S-Register Command Descriptions

56K V.92 Data, Fax, and Voice Chipset

7. S-REGISTERS

The MD566X chipsets provide direct access to the internal registers known as S-registers. The DTE uses S-registers to set up and check modem configurations. The contents of these registers can be changed using the ATSn=x command, where ‘n’ is the register number and ‘x’ is the value to be stored. The contents of the S-registers can be read using the ATSn? command. Most S- registers can be read from or written to; however, some S-registers (such as S14) are read-only. Writing to a read-only register may cause the modem to act improperly (that is, even though the contents of a read-only S-register may be changed using the ATSn=x command, changing the contents of the S-register does not normally configure the entire modem).

Reserved S-registers are used by the modem and provide no valuable information to the DTE. These registers have been removed from the following table. Reserved S-registers should never be written to, as they cause the modem to lock up.

Table 7-1. S-Register Command Descriptions

Note: An asterisk (*) denotes the factory-default setting.

Command Default Description

Number of Rings to Auto-Answer On: Assigning S0 a value from 1 to 255 config- ures the modem for auto-answer mode. The modem automatically goes off-hook and initiates a data mode-answer mode handshake after detecting the specified number of rings. This S-register is meant for data modem mode only and should be set to “0” for fax and voice modes.

Range: 0–255 rings

S0 0

n = 0 Auto-answer mode disabled

n = 1-255 Auto-answer mode enabled

NOTES:

1) If Caller ID is enabled (+VCID=n), then the modem only answers after the sec- ond ring even if S0=1.

2) Setting n > 2 causes the modem to answer on the nth ring signal.

		Ring Count: Reports the number of ring signals detected by the modem. This reg-
		ister is cleared to zero if no new ring signals are detected within an 8-second time
S1	0	interval.
		Range: 0–255 rings
		Default: 0 rings
		Escape Character: S2 specifies an ASCII value for the Hayes or TIES escape char-
		acter. The factory default is “+” or ASCII decimal 43. The escape character may
S2	43	range between 0–127. Any value over 127 disables the escape sequence.

Range: 0–127

Default: 43 (“+”)

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